Daryl Hart, 50, of Federal Way pleaded guilty to first-degree murder Monday.

Hart is accused of slaying a 70-year-old Seattle woman in 1984. According to the Associated Press, prosecutors claim Hart was 25 years old when he sexually assaulted and murdered his neighbor, Nora Gracey.

In August, the state’s crime lab returned DNA test results, showing Hart was the source of DNA collected following Gracey’s death, according to the Associated Press. Hart said he did not sexually assault Gracey. He is scheduled for sentencing Feb. 26.